Javier Hernandez is unsure how he will react if he opens his account for West Ham against former side Manchester United.

Former Manchester United striker Javier Hernandez is torn over whether he will celebrate if he scores for West Ham at Old Trafford.

Hernandez will return to Manchester for Sunday's Premier League opener, but in claret and blue, after joining West Ham from Bundesliga side Bayer Leverkusen.

The 29-year-old Mexico international left United two years ago, moving to Leverkusen after falling down the pecking order at the Theatre of Dreams, where he scored more than 50 goals in all competitions.

And Hernandez is unsure how he will react if he opens his account for new side West Ham on the weekend.

"I don't know if I will celebrate if I score at Old Trafford," he said. "It's my old club, my old fans, my old stadium but it'll be my first goal for West Ham.

"I am not thinking about the celebration, I just want to have the chance to start and get my team the result.

"I am very happy and glad, it's the best way to come back and open at Old Trafford.

"I am a Hammer, a West Ham player, I want to do even better than I did in Manchester."

Hernandez, who spent a season on loan at Real Madrid before exiting United permanently in 2015, added: "I never have regretted leaving Manchester United.

"I had some great experiences there and it helped me when I did move on."